feat(zsh): add tv cli options/arguments/subcommands autocompletion (#665)

## 📺 PR Description

update `init` shell generation to include autocompleting options for
`tv` itself.

<img width="817" height="497" alt="image"
src="https://github.com/user-attachments/assets/e65bc0aa-410e-43ef-86a5-2d6e01c6c1df"
/>

<img width="837" height="186" alt="image"
src="https://github.com/user-attachments/assets/6d9665f6-0664-4e6e-bce3-e6a970c79524"
/>

I've only tested this on macOS (arm64) with `zsh` and `bash` so far:

<img width="893" height="349" alt="image"
src="https://github.com/user-attachments/assets/dd66ecec-fee3-4713-a68c-f69e961a4ba6"
/>



## Checklist

<!-- a quick pass through the following items to make sure you haven't
forgotten anything -->

- [x] my commits **and PR title** follow the [conventional
commits](https://www.conventionalcommits.org/en/v1.0.0/#summary) format
- [x] if this is a new feature, I have added tests to consolidate the
feature and prevent regressions
- [ ] if this is a bug fix, I have added a test that reproduces the bug
(if applicable)
- [ ] I have added a reasonable amount of documentation to the code
where appropriate

---------

Co-authored-by: Alex Pasmantier <47638216+alexpasmantier@users.noreply.github.com>

Cargo.lock

@@ -305,6 +305,15 @@ dependencies = [
  "strsim",
 ]
 
+[[package]]
+name = "clap_complete"
+version = "4.5.55"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a5abde44486daf70c5be8b8f8f1b66c49f86236edf6fa2abadb4d961c4c6229a"
+dependencies = [
+ "clap",
+]
+
 [[package]]
 name = "clap_derive"
 version = "4.5.40"
@@ -1989,6 +1998,7 @@ dependencies = [
  "base64",
  "better-panic",
  "clap",
+ "clap_complete",
  "clap_mangen",
  "clipboard-win",
  "colored",

Cargo.toml

@@ -51,6 +51,7 @@ serde_json = "1.0.140"
 colored = "3.0.0"
 serde_with = "3.13.0"
 which = "8.0.0"
+clap_complete = "4.5.55"
 
 
 # target specific dependencies

television/utils/shell.rs

@@ -1,10 +1,11 @@
 use crate::{
-    cli::args::Shell as CliShell,
+    cli::args::{Cli, Shell as CliShell},
     config::shell_integration::ShellIntegrationConfig,
 };
 use anyhow::Result;
+use clap::CommandFactory;
 use std::fmt::Display;
-use tracing::debug;
+use tracing::{debug, warn};
 
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub enum Shell {
@@ -28,6 +29,31 @@ impl Default for Shell {
     }
 }
 
+#[derive(Debug)]
+pub enum ShellError {
+    UnsupportedShell(String),
+}
+
+impl TryFrom<Shell> for clap_complete::Shell {
+    type Error = ShellError;
+
+    fn try_from(value: Shell) -> std::result::Result<Self, Self::Error> {
+        match value {
+            Shell::Bash => Ok(clap_complete::Shell::Bash),
+            Shell::Zsh => Ok(clap_complete::Shell::Zsh),
+            Shell::Fish => Ok(clap_complete::Shell::Fish),
+            Shell::PowerShell => Ok(clap_complete::Shell::PowerShell),
+            Shell::Cmd => Err(ShellError::UnsupportedShell(
+                "Cmd shell is not supported for completion scripts"
+                    .to_string(),
+            )),
+            Shell::Nu => Err(ShellError::UnsupportedShell(
+                "Nu shell is not supported for completion scripts".to_string(),
+            )),
+        }
+    }
+}
+
 impl Display for Shell {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
@@ -143,6 +169,7 @@ pub fn render_autocomplete_script_template(
     template: &str,
     config: &ShellIntegrationConfig,
 ) -> Result<String> {
+    // Custom autocomplete
     let script = template
         .replace(
             "{tv_smart_autocomplete_keybinding}",
@@ -158,7 +185,33 @@ pub fn render_autocomplete_script_template(
                 config.get_command_history_keybinding_character(),
             )?,
         );
-    Ok(script)
+
+    let clap_autocomplete =
+        render_clap_autocomplete(shell).unwrap_or_default();
+
+    Ok(script + &clap_autocomplete)
+}
+
+fn render_clap_autocomplete(shell: Shell) -> Option<String> {
+    // Clap autocomplete
+    let mut clap_autocomplete = vec![];
+    let mut cmd = Cli::command();
+    let clap_shell: clap_complete::Shell = match shell.try_into() {
+        Ok(shell) => shell,
+        Err(err) => {
+            warn!("Failed to convert shell {:?}: {:?}", shell, err);
+            return None;
+        }
+    };
+
+    clap_complete::aot::generate(
+        clap_shell,
+        &mut cmd,
+        "tv", // the command defines the name as "television"
+        &mut clap_autocomplete,
+    );
+
+    String::from_utf8(clap_autocomplete).ok()
 }
 
 #[cfg(test)]
@@ -208,4 +261,30 @@ mod tests {
         assert!(result.is_ok());
         assert_eq!(result.unwrap(), "Ctrl-s");
     }
+
+    #[test]
+    fn test_zsh_clap_completion() {
+        let shell = Shell::Zsh;
+        let result = render_autocomplete_script_template(
+            shell,
+            "",
+            &ShellIntegrationConfig::default(),
+        );
+        assert!(result.is_ok());
+        let result = result.unwrap();
+        assert!(result.contains("compdef _tv tv"));
+    }
+
+    #[test]
+    fn test_unsupported_clap_completion() {
+        let shell = Shell::Nu;
+        let result = render_autocomplete_script_template(
+            shell,
+            "",
+            &ShellIntegrationConfig::default(),
+        );
+        assert!(result.is_ok());
+        let result = result.unwrap();
+        assert!(result.is_empty());
+    }
 }